All nuclear reactor systems must interface with the environment through an adsorbent system, normally charcoal, and a high efficiency particulate filter. Iodine.sup.131 is one of the important fission-product gases that must be trapped from reactor air streams; some of this nuclide is in the form of methyl iodide.
In efforts to remove this fission-product certain impregnated charcoal products have been used. Of particular interest has been triethylene diamine (TEDA) because of the rapid rate of reaction of this inpregnant with air borne methyl iodide. However, even higher reaction rates are desired.
In addition to adsorption characteristics, a very important property of impregnated charcoals is the magnitude of the spontaneous ignition temperature. In general, impregnated charcoals ignite at temperatures considerably below that of the base charcoal, usually in the neighborhood of the flash point of the impregnant.